Thread-stitching machine for bookbinding.



U. B|SCHOF..

THREAD STITCHING MACHINE FOR BOOKBINDING.

APPLICATION FILED JUNE 3,1915.

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' 1 ,235,099. Patent 6d July 31, 1917.

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u. BI SCHOFQ THREAD STITCHING MACHINE FOR BOOKBINDING. I

APPLICATION HLED JUNE 3,1915- Patented July 31, 1917.

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ATTX' UNIT @TATES ATET ULRICH BISCHOF, OF WINTERTI-IUR, SWITZERLAND, ASSIGNOR T0 GEBR. STAUBLI, I-IORGEN, Sl/VITZERLAND.

THREAD-STITCHING MACHINE FOR- BOOKBINDING.

Specification of Letters Patent.

Patented July 31, 1917.

Application filed June 3, 1915. Serial No. 31,961.

To all whom it may concern:

Be it known that I, ULRICH BISCHOF, a citizen of the Republic of Switzerland, residing at Winterthur, in the Canton of Zurich, Republic of Switzerland, have invented certain new and useful Improvements in Thread-Stitching Machines for Bookbinding; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same, reference being had to the accompanying drawings, and to letters of reference marked thereon, which form a part of this specification.

My invention relates to thread-stitching machines for book-binding and particularly to an arrangement of a thread layer. Thread layers in thread-stitching machines, in which a separate thread embraces each individual stitch, ties and draws the same outwardly at another place through the back of the sheet, are known. When the tying loop is then released, it will be tightened, so that also the thinnest sheets may be stitched to be perfectly tight.

In thread-layers of the kind as above described it may happen that both branches of the stitch-loop are taken by the hookneedle and that the stitch-loop therefore will fall out, because the branches of the stitchloop pulled out by the thread-layer lie side by side in different planes.

With the single-pointed thread-layer according to my invention this disadvantage is avoided by the fact that the branches of the stitch-loop extended by the threaddayer will be placed one over another in one and the same plane so that only the stitch-loop and of this loop only one branch will be seized by the hook-needle after the stitchloop has been drawn through the tyingloop, so that when the thread is tightened the tying-loop surrounds and ties the stitchloo II structure embodying my invention and illustrating the principles thereof is shown in the accompanying drawings and will be hereinafter fully described and referred to in the appended claims.

In the drawings, Figure 1 is a view in elevation showing the single-pointed threadlayer. Fig. 2 is partly a plan and partly an end view of a cam-plate. Figs. 3, 4,

5, 6, 7 and 8 are diagrammatic views showing the function of the thread-layer. Figs. 9, l0 and 11 are cross-sections of the machine also showing the thread-layer in different positions. Figs. 12 and 13 are diagrammatic views of book-backs with the stitching.

The thread layer 1 has a single point 2, an upper thread rest 3 and a lower thread rest 1 and it is secured to a rocking shaft 5, as indicated in Figs. 9, 10 and 11. This shaft 5 carries also a lever 6 provided with an anti-friction roller 7 pressed upon a stationary cam plate 8 by a spring 7 as seen more clearly in Figs. 2 and 9 to 11. The steps I, II, III and IV of this cam plate determine the angle of oscillation of the shaft 5 and by this also of the threadlayer.

The operation of the thread-layer is as follows:

As soon as the sheet is passed under the needles, 9, 12, 14 the latter penetrate the fold of the sheet and move back somewhat, in order to form the loops, see Fig. 9. In Figs. 3 and 9 the thread-layer is shown in the initial position, at the left hand of the first eyed sewingaieedle 9 whereby the roller 7 rests upon the step I. Now the threadlayer 1 moves to the right and seizes the thread-loop 10 previously formed see Figs. 4 and 9. Immediately afterward the roller 7 comes upon the lower step II of the camplate 8, so that the thread layer is caused to perform a slight oscillation backward, as shown in Fig. 10. When the thread-layer continues to move to the right from the position shown by Fig. l to that shown by Fig. 5, it remains in the back position. By this the upper branch 10 of the thread loop, see Fig. 5, comes in front of the thread layer and in the thread rest 3, while the lower shank 11 of the thread loop engages the thread rest 4. Thus the two branches l0 and 11 of the thread loop are considerablv separated one from the other and placed one over the other in the same plane, as shown by Figs. 6 and 7. When the thread layer 1. further advances to the right from the position shown by Fig. 5 in that shown by Fig. 6, the roller 7 reaches the step III of the cam plate 8 and swings the thread layer forward in the initial position, shown by Fig. 11. In this position the thread-layer stands immediately before the second eyed sewing-needle 12, see Fig. 6, and when the thread-layer advances still more to the right, the thread-layer seizes the thread-loop 13 of the second sewing needle 12, which loop comes in the thread rest 4, in which is placed the branch 11 of the first thread loop, as shown by Figs. 7 and 8. When the thread layer seizes the second. thread loop it is not moved backward. As the first thread loop 10 11 is passed through the second thread loop 13 the former is tied by the latter. As soon as the first and the sec ond loop will be perfectly extended (see Fig. 8), the roller 7 runs upon the step IV of the cam plate 8 and swings the thread layer slightly toward the hooked needle 14, which when it raises seizes the stitch-loop. Since the two branches 10 and 11 of the stitch-loop lying in the rests 3 and 4: are greatly separated one from the other and arranged one over the other, the hooked needle can only seize the upper branch of the stitch-loop, the seizing of both the branches of the said loop being surely avoided.

The hooked needle then draws the stitchloop through the sheet and at the same time the thread-layer 1 returns to its initial position, whereby the tying loop 13 embracing the stitch loop 10 is released. Finally also the tying loop 13 is tightened.

Fig. 12 diagrammatically shows a back of a book stitched by a double set of needles and thread layers in the machine as described.

If it is desired to stitch upon a band or gauze, one of the sewing needles is reciprocated in a known manner and the fabric thereby stitched to the back of the book by a zig-zag stitch.

Fig. 13 shows a back of a book, stitched in such a manner that the sewing needles have not been shifted laterally to sew the bands or the gauze, but in which a separate thread 15 has been put in a known manner in a zig-zag stitch over the back of a book, so that it has been fastened to the book by the two sewing needles.

Other means may be used to impart a rocking motion to the thread layer.

Having described my invention, I claim 1 1. In a thread stitching machine, the combination with eyed sewing needles and a hooked needle of a single pointed thread. layer having two thread rests separated by the beak of the thread layer and means for imparting to the latteran. oscillation transversely to the plane of the needles during the extending action of the thread layer to bring both the branches of the stitch loop upon the same side of the thread layer and intothe said thread rests.

2; In a threadstitching-machine, the com-- bination with a pair of eyed sewing needles and a hooked needle of a single pointed thread layer having'two thread rests separated by the beak of the thread layer, a rocking shaft carrying the thread layer and a. depending arm, a stationary cam plate parallel to-the said rocking shaft and haw ing a number of steps and a spring pressing the said armw th cam plate.

8. Ina thread stitchingmachine, the combination with a: pair of. eyed sewing needles and a hooked needle of a single pointed thread layer having twothread rests separatedby the beak. of the thread layer, a rocking shaft carrying the thread. layer and a depending arm, provided with an antifriction roller, a stationary cam plate parallel to the said rocking shaft and having a number of steps and: a spring pressing the said arm tothe cam plate.

In testimony whereof, I have signed my name tothis specification in the presence of two subscribing witnesses.

ULRICH BISCHOF.

WV-itnesses HERMANN HUBER, CARL GUBER.

Copies of this patent may be obtained for five cents each; by addressingthe Commissioner of Patents, Washington, D. G. 

